In the construction of boilers and other heat exchange equipment, used in the power generation and chemical industries, there is a need for a device which can be used to form a seal for tubes, pipes and similar conduits which transport steam, liquid or gasses under pressure. The requirements for such devices include ease of installation, relatively low cost, and the ability to maintain a seal against leakage of steam, water or other gasses or fluids, over an extended period of time, with a high degree of reliability. One of the typical requirements for such tubes is that they have a relatively thin wall in order to maximize the rate of heat transfer through these tubes. This relatively thin wall structure results in an additional requirement for an effective tube plug. Such a device must not cut into the tube wall, or in any way weaken the structure of the tubes in order to prevent degradation of the tube's resistance to failure under pressures.
It is an object of the present invention to provide a tube plug which can be quickly and easily installed in the end of a tube, usually within a heat exchanger tube sheet, to provide an effective leakproof seal.
Another object of the present invention is to provide a tube seal capable of withstanding operational pressures.
Another object of the present invention is to provide a tube plug which can provide a seal against both liquids and gasses.
Another object of the present invention is to provide a tube plug which does not weaken the tube during or after installation.
Still another object of the present invention is to provide a tube plug comprising a relatively small number of simple component parts resulting in a relatively low manufacturing cost.